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排序方式: 共有762条查询结果,搜索用时 140 毫秒
1.
Dongdong Ji Zheng Liu Bailing Jiang Xiaofei Luo 《International Journal of Hydrogen Energy》2021,46(27):13960-13970
The evaluation of cell's weatherability is of practical interest. To further improve the soluble lead flow battery's weatherability, physiochemical properties of electrolytes containing fluoborate, perchlorate, methanesulfonate and trifluoromethanesulfonate are investigated from ?60 to 50 °C. Activities of CF3SO3H and HClO4 are poor in trifluoromethanesulfonate and perchlorate solutions due to common anion effect. The solubility of lead salt can be improved by increasing temperature, but worsened by increasing acid's content. With the temperature increasing, the conductivity is enhanced, and the viscosity is lowered for four solutions. The same results have been found by increasing acid's content except for CF3SO3H. The high energy efficiency can be achieved for cells over ?40–0 °C using fluoborate and perchlorate solutions, 73.2% at ?40 °C and 78.1% at ?30 °C respectively. Over the temperature range of 20–50 °C, the cells with methanesulfonate and trifluoromethanesulfonate solutions have good performance, 77.4% and 73.7% at 50 °C respectively. 相似文献
2.
Jeong Ha-Ram Cho Hye-Seung Cho Youn-Sup Kim Dae-Ok 《Food science and biotechnology》2020,29(12):1763-1770
Food Science and Biotechnology - Hardy kiwifruits (Actinidia arguta) contain various bioactive compounds such as vitamin C and phenolics and can withstand cold temperatures. Changes in soluble... 相似文献
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水溶性涂料使用性能研究 总被引:1,自引:0,他引:1
本文通过试验对水溶性涂料的耐盐雾腐蚀性能,耐热性能,高低温冲击性能,耐油性能,涂膜与铁基体,面漆的给合力及涂膜表面电阻进行研究,同时指出了该涂料在军用电子产品上的应用前景。 相似文献
5.
离子色谱技术在钻井现场的应用研究 总被引:1,自引:0,他引:1
将离子色谱技术(IC)应用于钻井现场的钻井液滤液分析,从而获取所钻井钻遇地层的可溶性矿物的性质、地层水的类型等资料信息。离子色谱技术在这一领域的应用尚属探索阶段,但通过现场两口井的试用已见到较好的应用效果,文章简介了该技术的应用前景及价值,如:确定油水界面的位置及指导钻井液的调配、确保井下安全等。这方面的论述,对分析化验仪器向井场转移实现多手段综合分析具有一定的促进作用。 相似文献
6.
本文应用贝尔德DV—5光谱仪对钢中微量酸溶铝的测定进行了研究,通过优化仪器参数和控制分析条件等手段,用二次预燃和二次曝光测定酸溶铝,检出限可达0.0015%,该法简便、快速、结果准确。 相似文献
7.
重组人白细胞介素-10在大肠杆菌中的表达及生物学活性分析 总被引:1,自引:0,他引:1
目的在大肠杆菌中表达重组人白细胞介素-10(Interleukin-10,IL-10),并检测其生物学活性。方法将IL-10基因重组到质粒pET11c中,转化BL21(DE),提取质粒,经酶切鉴定和测序分析;在25℃用低浓度的IPTG诱导表达,对包涵体IL-10稀释复性;经ELISA检测其含量,MC/9细胞增殖法检测其生物学活性。结果工程菌IL-10/pET11c/BL21诱导表达的目的蛋白以可溶性和包涵体两种形式存在,Westernblot鉴定证实为IL-10蛋白,两种形式的IL-10均具有一定的生物学活性。结论已成功地在大肠杆菌中表达了IL-10,为进一步纯化和制备IL-10的基因工程药物打下了基础。 相似文献
8.
Christos L. Chochos Giannis K. Govaris Fotini Kakali Joannis K. Kallitsis Vasilis G. Gregoriou 《Polymer》2005,46(13):4654-4663
New copoly(arylether)s containing substituted terphenyl, quinquephenyl, fluorene and anthracene moieties with aromatic 1,3,4-oxadiazole units were prepared and the resulting copolymers are soluble in common organic solvents. Investigation of their optical properties revealed that they emit blue and yellow light. Moreover, their photovoltaic response was studied in blends with poly(3-hexylthiophene) (P3HT) as the electron donor. Despite the low power conversion efficiencies it was shown that photo-induced electron transfer does take place and the performances are higher than a single layer P3HT device. In addition, an anthracene-fluorene-oxadiazole main chain copolymer (PAFOXD) was also examined in a single layer photovoltaic device and gave one of the highest reported open-circuit voltage (Voc) values in the literature (0.89 V). Finally, a detailed morphological study of the blends and the PAFOXD surface using the atomic force microscopy (AFM) technique, revealed the effect of solvent selection to the preparation of thin films exhibiting the desired performance characteristics. 相似文献
9.
Two tetracarboxylic dianhydrides with polyalicyclic structure, bicyclo[2.2.2]octane-2-endo, 3-endo, 5-exo, 6-exo-2,3:5,6-dianhydride (5a) and the all-exo isomer (5b), were synthesized in six steps using phthalic acid as a starting material. The dianhydrides were polymerized at 85–105°C in well-purified DMAc with aromatic diamines which were purified by two recrystallizations and then sublimation. The polyimides formed flexible and tough films, and were soluble in aprotic polar solvents such as DMAc. The 5%-weight loss temperatures were over 450°C. The polyimides possessed glass-transition temperatures in the range from 211 to 385°C. The polyimides films had a tensile modulus range of 1.5–2.6 GPa, a tensile strength range of 52–96 MPa, and an elongation range at break of 3–11%. The polyimide films showed cutoffs at wavelengths shorter than 320 nm and were entirely colorless. The colorlessness of the polyimide films was maintained up to 200°C when heated in air and to 400°C in a N2 atmosphere. 相似文献
10.
对江西 1 1种母质发育的有代表性的水稻土、旱作地、自然土壤 ,61个剖面 ,4 1 2个土样的可溶态稀土元素分析测定 ,统计结果表明 :江西土壤稀土元素的强度因素处于较高水平 ,平均值为 1 9 0mg/kg ,有 4 2 80 %的样点处于丰富级 ;有由南向北 ,由东向西逐渐降低的趋势 .其含量最高的地区是赣南由花岗岩、泥质岩、第四纪红粘土、酸性紫色土、碳质岩类风化物等母质发育的土壤 ,较低的为赣西北由石英岩 ,第三纪红砂岩、石灰岩、下蜀系黄土等母质发育的土壤 ;在土壤剖面分布中 ,旱作地表层低于底层 ,水稻土表层有生物富集作用高于底层 ;影响土壤中可溶态稀土元素含量的主要因子有 :成土母质 ,气候条件 (温度 ,降水量 ) ,土壤 pH ,土壤质地和耕作类型 相似文献